Photoelectric device grinding process and device grinding process

Abstract

A photoelectric device grinding process comprising the following steps is disclosed. A wafer comprising a plurality of chip units is provided. Each chip unit has at least a photoelectric device disposed on a surface layer. A dielectric substrate is attached to the wafer with glue having a plurality of spacers therein such that the photoelectric devices face the dielectric layer. The spacers maintain a gap between the dielectric substrate and the wafer. Thereafter, the dielectric substrate surface away from the wafer or the wafer surface away from the dielectric substrate or both is ground. The grinding process is particularly suitable for preventing any possible damage to the photoelectric devices on a wafer.

1. A photoelectric device grinding process, comprising the steps of:
 providing a wafer having a plurality of chip units thereon, wherein the surface of each chip unit has at least a photoelectric device; 
 providing an amount of glue with a plurality of spacers therein; 
 attaching a dielectric substrate over the photoelectric device on the surface of the wafer through the glue, wherein the glue and the spacers are disposed between the dielectric substrate and the wafer and both of the glue and the spacers are directly contacted with the dielectric substrate and the wafer, such that the spacers maintain a constant gap between the dielectric substrate and the wafer and the spacers are surrounded by the glue except for the portion of the spacers directly contacting the dielectric substrate and wafer; and 
 after attaching the dielectric substrate over the photoelectric device on the surface of the wafer, grinding the surface of the dielectric substrate away from the wafer or the surface of the wafer away from the dielectric substrate. 
 
     
     
       2. The photoelectric device grinding process of  claim 1 , wherein the photoelectric device comprises an image sensor. 
     
     
       3. The photoelectric device grinding process of  claim 1 , wherein the glue comprises ultraviolet cured plastic. 
     
     
       4. The photoelectric device grinding process of  claim 1 , wherein the material constituting the spacers comprises silicon oxide. 
     
     
       5. The photoelectric device grinding process of  claim 1 , wherein the step of grinding the dielectric substrate or the wafer comprises mechanical grinding. 
     
     
       6. The photoelectric device grinding process of  claim 1 , wherein the dielectric substrate comprises a glass substrate or a silicon substrate. 
     
     
       7. The photoelectric device grinding process of  claim 1 , wherein the glue, each chip unit and the dielectric substrate together form at least a sealed chamber such that the photoelectric device is enclosed within the sealed chamber. 
     
     
       8. The photoelectric device grinding process of  claim 1 , wherein the photoelectric device comprises a micro-mechanical structure. 
     
     
       9. The photoelectric device grinding process of  claim 8 , wherein the micro-mechanical structure protrudes from the surface of the wafer by a height smaller than the gap between the dielectric substrate and the wafer.